Butadiene-acrylonitrile copolymer plasticized with isobutyl beta isobutoxy propionate



Patented Feb. 10, 1948- UNI-TED sr T BUTADIENE-ACRYLONITRILE coronmma PLASTICIZED WITH ISOBUTYL BETA ISO- BUTOXY PROPIONATE Albert M. Clifford and Joy G. Lichty, Stow, Ohio,

assignors to Wingfoot Corporation,

Akron,

Ohio, a corporation of Delaware No Drawing. Application November 12, 1943, Serial No. 510,034

1 Claim. 1

This invention relates to a plasticized, synthetic rubber and is particularly suited for use in compounds which are to be used at very low temperatures. The plasticizer is an alkyl ester of a beta alkox propionic acid. The preferred plasticizer is isobutyl beta isobutoxy propionate. When used to plasticize a synthetic rubber which is essentially composed of butadiene and acrylonitrile, it has been found to give a plasticized product which remains flexible at very low temperatures.

The following examples illustrate the invention. The compounding formulae are first given. The various materials are given in parts by weight. Following the respective formulae are tables showing the testing data acquired in the usual manner from rubber compounded according to the preceding formulae. The tensile and modulus values below are given in kilograms per square centimeter which may be converted to pounds per square inch by multiplying these values by the conversion factor 14.2.

when tested according to the usual cold test, the

tes4t sample was satisfactorily bent double at Cure Tensile ggg Modulus- 5 1o min/290C 42 885 min/290 0.- 127 590 so min/290 0.. 121 49s 47 40 mi1l./290 0.- no 450 51 60min./290 0 110 440 as 10 Example 3 Copolymer 110.0 Zinc (wide 1.0 Sulfur 0.1 Gas black 45.0 15 Tetramethyl thiuram disulfide- 3.0 Isoamyl beta isoamyloxy propionate 23.0

Cure Tensile igg %%g 109 525 43 us 480 51 so 410 54 25 Example 4 Copolymer 110.0 Zinc oxi 5.0 Sulfur 2.0 Gas 1112 0k 75.0 Benzothiazyl-2-diethylsulphenamide 1.0 Stearic acid 1.0 Isoamyl isoamyloxy propionate 45.0

. El M dul Cure Tensile 8E5 2o min/290 o to 41a 46 4o min.l290 96 390 at 60minJ290 o 94 355 72 Example 2 Butadiene-1,3/acrylonitrile c o p 01 y m e r /40 110.0 Zinc oxide 1 Sulfur 0.1 Gas black 35.0 Tetramethyl thiuram disulflde 3.0 Isobutyl beta isobutoxy propionate 18.0

The above formulae are merely illustrative. The ingredients and the amounts of each may be varied. The amount of plasticizer used may be varied over a wide range.

The alkyl groups, as will be seen, may contain from, for example, one to twelve carbon atoms. Different alkyl groups may occur in any of the compounds. The esters of this class are all good plasticizers for this rubber-like copolymer although the isobutyl ester of the isobutyl ether is 3 preferred when the rubber material is to be used UNITED STATES PATENTE at real low temperatures. Number Name Date What We 4 2,010,154 Hubacher Aug, 6, 1935 A rubber-hke copolymer of butadlene and acry- 2 051 877 Marks Aug 25 1936 lonitrile plasticized with isobutyl beta isobutoxy 5 2245233 smith 194i propionate. M. an NOV. 27, JOY G. LICHTY. OTHER REFERENCES SIFDQkJ-ill, 1713435. 11151311 Rubber :IQd V01. 15,

0 pages 52 aid 58, June 1939.

The following references are Ofrecord inthe file of this patent:

'Hycar OCR. 15, Softener Stu'dy' 2A, Sept. 1942, pages 6, 7 and 20. 

